Microbial Enzymes and Their Industrial Applications

Abstract

Enzymes are biological catalysts produced in living cells. They are proteinaceous in nature, the exception being catalytic RNA, which are also referred to as ribozymes. The term ‘en zyme’ is derived from the Greek, meaning ‘in sour dough’. E. Buchner (1897) experimentally proved that cell-free extract from yeast could produce alcohol from sugars, and he referred to it as “zymase”. The unique characteristics that enzymes possess are that they (1) increase the rate of reaction they catalyze, without being consumed or lost; (2) act specifically with the substrate to produce the products; and (3) remain regulated from a state of low activity to high activity and vice versa. Enzymes have been grouped into six classes based on the types of reactions they catalyze (Table 9.1). All cellular processes are controlled by a coordinated sequence of reactions that have specifically been catalyzed by a defined set of enzymes.